Isis Pharmaceuticals and Sanofi’s Genzyme subsidiary said today they are gearing up for launch later this year of their new injectable drug Kynamro™ (mipomersen sodium) for a rare inherited disease in which the body cannot remove LDL cholesterol from the blood, following FDA approval yesterday of its New Drug Application.
Kynamro was approved in the form of a 200 mg weekly injection as an adjunct to lipid-lowering drugs and diet to reduce low-density lipoprotein-cholesterol (LDL-C), apolipoprotein B (Apo B), total cholesterol (TC), and nonhigh-density lipoprotein-cholesterol (non HDL-C) in patients with homozygous familial hypercholesterolemia (HoFH).
HoFH is an orphan indication linked to high cholesterol levels leading to heart attacks and even death by age 30, and occurs in approximately one in 1 million people. Kynamro is the second treatment approved for HoFH approved in recent weeks. Last month, FDA granted marketing authorization to Aegerion Pharmaceuticals’ Juxtapid (lomitapide) to reduce LDL-C, total cholesterol, apolipoprotein B, and non HDL-C in patients with HoFH.
“It shows we can develop drugs that have the potential to bring profound benefit to patients who have a lifelong chronic disease, and are in need of new therapeutic alternatives,” Stanley T. Crooke, M.D., Ph.D., Isis’ chairman of the board and CEO, this morning during a conference call with analysts. “This is a seminal day for Isis, and it is a seminal day for the technology, the drug discovery platform, that we at Isis have pioneered.”
In a statement, Dr. Crooke noted that Kynamro is the first of several systemic antisense drugs to reach the market and was the culmination of two decades of work.
The FDA approval will result in a $25 million milestone payment to Isis from Genzyme, which has served as development and regulatory partner to Isis for Kynamro.
FDA approved Kynamro after its safety and effectiveness of were evaluated in the largest-ever clinical trial of HoFH patients, consisting of 51 patients aged 12 to 53 years—including 7 patients age 12 to 16 years—with HoFH. In results of the trial published in The Lancet in 2010, LDL-C levels fell on average by about 25% during the first 26 weeks in patients receiving the drug.
However, Kynamro will carry a Boxed Warning cautioning patients on the drug’s serious risk of liver toxicity because it is associated with liver enzyme abnormalities and accumulation of fat in the liver, which with chronic use could lead to progressive liver disease.
Because of the risk of hepatotoxicity, FDA also required that Kynamro undergo a Risk Evaluation and Mitigation Strategy (REMS) to assure safe use. REMS requirements include prescriber and pharmacy certification, and documentation of safe-use conditions, which requires a prescription authorization form for each new prescription.
How quickly Kynamro undergoes the additional REMS, and which managed-care plans cover patients, will determine how quickly the new drug reaches the market and rings up its first sales, Paula Soteropoulos, vp and general manager of Genzyme's Cardiovascular Business, told analysts on the conference call.
“It could be four weeks, six weeks, but it could be less. It truly depends on that combination of the timing for REMS and the managed care,” Soteropoulos said, adding, “When we get that through the process, we’re ready to get the product to the patient.”